1. Field of the Invention
This invention generally relates to fluid couplings and more particularly to a self-sealing, quick disconnect (QD) cap for a male coupling to isolate it from external pressures.
2. Description of the Prior Art
Standard self-sealing couplings for fluids are designed to seal themselves from internal pressures only. However, in a Vertical Launch System (VLS), the missile tube has a quick disconnect coupling located therein. When a Capsule Launch System (CLS) is loaded into the missile tube, a sensing line from the CLS is connected to the QD coupling forming a path from the missile tube's differential pressure transducer to the CLS. However, when a ballast cam is loaded into the missile tube in place of a CLS, no sensing line is connected to the missile tube's QD coupling and the QD coupling's self-sealing plunger could be subjected to an external pressure. This situation can arise in the event of a flooded tube. If the plunger is opened under this circumstance, it would subject the different pressure transducer to sea pressure which would destroy it. There is thus a need for a pressure cap on the coupling which protects the differential transducer and the QD coupling against an external pressure.